I'll be interested in seeing what other answers you get to this question. Phil grad programs vary widely in reputation, as well as in both entrance and graduation requirements. There's also variation in the quality of work that gets published, as well as the amount and venue of publication that will count, in the eyes of colleagues and potential employers, as a "significant contribution to the field." I consider myself a constructive contributor every time I answer a question on this site or help a previously befuddled undergrad distinguish between a sound argument and a fallacious one...though the American Philosophical Association would probably be inclined to disagree.
For insight into programs and their respective requirements, see University of Texas professor Brian Leiter's Philosophical Gourmet Report, especially the links on Graduate Study. For insight into the process of getting through graduate school and into a philosophy professorship, see A Philosophy Job Market Blog, with particular attention to the comments.
If you and I were having this conversation one-to-one over a cup of coffee, I'd say: I felt I earned my degree when I got it, twelve years after starting graduate study. As for my university position, I gladly acknowledge it was more a matter of luck than earning, though I do feel I earn it with every student paper I grade. (You can find insight into these answers on my own blog, The Philosopher-Mom, although it will require some searching and a sense of humor.)
In the end, I'd say, don't do it unless you love philosophy. Period.